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WiMax: you have the spectrum. But what about planning permission?

A very large comms corporation is kissing babies, preparatory to launching something new next week. Details are under embargo, but my chat with them this week provoked an enthusiastic discussion about whether 802.16e really is useful in mobile telephony.

We ended up agreeing that in the UK, Europe, and America, the problems of setting up the infrastructure really made WiMAX a marginal product for the next two years. That, of course, leaves Africa, much of South America, and some of the developing parts of Asia. We decided that there is, definitely, enough of a market there to make a launch worthwhile.

Exactly what will be launched is what I have to keep under wraps, but suffice it for now to say that a hybrid product is involved, and it won't involve standard GSM or CDMA mobile wireless. As to what it will involve, you are at liberty to guess that WiMAX might come into it...

The WiMAX technology has been heavily hyped. Intel, in particular, wants to see it become an absolute standard, with WiMAX wireless on every laptop computer. For that to work, it has to be a wireless network available everywhere in the world.

WiMAX comes in several flavours, of course, but if we ignore the Korean WiBro version, it's fixed (802.16d) and mobile (802.16e) and the mobile is, according to the PR machinery, now in full "approved, rolling out" mode.

A quick check of the archives shows that this isn't the full picture. If it was, there would be no need for the 802.20 standard. But that doesn't mean that 16e is useless. It may, in fact, be quite handy for small, rural communities.

Exactly why anybody would want to use 802.16e - mobile WiMAX - for mobile phones, may need some explaining. There are disagreements about this, and it's hard to be sure when people are offering technical arguments or political ones.

The infrastructure needed to roll out WiMAX in London is daunting. My friends estimate that you'd need a transceiver node - a cell - at a rate of several hundred per square mile. Admittedly, they'd be (technically) possible to locate on top of lamp-posts.

My objection was just troublemaking, I suppose. I said the problem with WiMAX is that it can't be licence free.

Originally, Intel launched WiMAX as something that would run at 2.4 GHz in the licence free zone of the spectrum map, where anybody can buy the equipment and plug it in. We're starting to see the drawbacks of this as Wi-Fi channels run out in 2.4 GHz and people are having to switch to 802.11a for speed, to avoid congestion. All proponents of WiMAX now seem to accept that it has to be a licensed spectrum, and it's over to the technical politicians to select the best wavebands...but there's a problem with putting up licensed radio transmitters for comms - planning permission.

I get spammed by the mast debaters all the time, and perhaps I'm jaundiced because of the poor logic they use; but just because I don't think there's any evidence of "wireless smog" causing harm to humans, we can't suddenly dismantle the law requiring planning applications. And - whether the law is justified or not - while it's there, people will oppose masts, and local councils will drag their feet in giving permission.

If it comes to court and someone shows that WiMAX does not need planning permission, we can move forward; till then, it's something I worry about. But that's not something that's likely to bother a small rural community of 2,000 people in central Africa.

Also, the density of cells in rural communities doesn't have to match what you'd need to provide high speed mobile internet to cosmopolitan groups in high density suburbs.

Paradoxically, the problems with mobile hand-off that are plaguing 802.16e (and which led to 802.20 working groups in the IEEE) don't affect voice as badly as high speed data, according to engineers I've talked to in the last couple of weeks. This isn't a statement everybody agrees with, of course. But a brief re-synch between handset and mast may make only a click in the ear during a voice call - and it may disrupt a data call quite badly, my sources insist.

I've written before about the fact that WiMAX uses a lot more power than GSM or WCDMA mobile phones, and pointed to the fact that Intel has sold off its Xscale chip range as a sign that it is focusing on WiMAX applications in the power-rich PC notebook environment, and not expecting to see the technology in phones. But you have to consider that if you cut the data rate from "like broadband" to "like GSM" the battery drain could be enormously reduced.

So although there are real problems with making mobile WiMAX handsets, the problems may be of importance only in the West, and of small consequence to someone in the Philippines or Madagascar or remote parts of Tibet...and, of course, much of China.

In two years, Moore's Law will solve the 802.16e mobile hand-off problem. It is, in theory, solved. It just takes far more computer power than you'd put in a handset in 2007. In the meanwhile, the theory goes, anybody planning to sell WiMAX gear is probably going to cover their setup costs and find out the bugs and glitches profitably, by providing telephone "exchanges" to third world communities.

Expect to hear more before the coming 3GSM Congress in Barcelona, and expect it to be from someone other than Qualcomm or Intel.